1. Field of the Invention
The present invention relates to a screwdriver, more specifically, to a ratchet device and screwdriver.
2. Description of the Related Art
Currently, screwdrivers are used for fastening or loosing screws, which bring a great convenience for people. In the prior art, a screwdriver comprises a screwdriver handle, a screwdriver body and a screwdriver head. The screwdriver body and the screwdriver head are immobilized in one piece. People should keep loosing and fastening their hands when they use this screwdriver, which enables the hands in a suitable place to exert force. However, these motions will be likely to cause the screwdriver head to be broken away from the screw, and thus operation to the screwdriver is quite inconvenient.
The Chinese patent (application number: 201010107089.3 application date: 2010 Feb. 8) disclosed a ratchet screwdriver in which a ratchet is arranged. The ratchet screwdriver comprises a pawl base, a ratchet shaft, a outer clamping ring and two pawls; wherein the two sides of a central shaft hole of an annular body of the pawl base are respectively provided with an installation opening for mounting, the pawls, the pawls are respectively arranged in the installation openings; the ratchet shaft, the outer clamping ring and the pawl base are connected into a whole by the ratchet shaft. The pawls are in the shape of arch type and are provided with dummy clubs and ratchets. The ratchet shaft is provided with strip teeth. Compression springs enabling the ratchets to be engaged with the strip teeth are respectively arranged in the installation openings. The inner surface of the outer clamping ring is provided with two notches. An inclined plane is arranged on the notches. When the outer clamping ring is rotated towards one side, the inclined plane can oppress the dummy club on one of the pawls so that the ratchets on the pawl can be disengaged from the strip teeth.
Therefore, most of the screwdrivers oppress the pawl by using the recess opening of the outer clamping ring, thereby disengaging the ratchet from the strip teeth.